Python 自定义一个 异常


有时候,我们会遇到 系统自带的 异常不够用.

Python 提供了自定义异常类型


#!/usr/bin/env python
# encoding: utf-8

class ShortInputException(Exception):
	def __init__(self, length, atleast):
		self.length = length
		self.atleast = atleast
try :
	s = raw_input('Enter something -->')
	if len(s) < 3:
		raise ShortInputException(len(s), 3)
except EOFError:
	print '\nWhy did you do an EOF on me?'
except ShortInputException, x:
	print 'ShortInputException: The input was of length %d, \
              was expecting at least %d' % (x.length, x.atleast)
else :
	print 'No exception was raised.'